Do We Really Need That Pre-ACTH Cortisol? Large UK Study Challenges Standard Addison's Testing Protocol

If you've been practicing for any length of time, you've run countless ACTH stimulation tests. The protocol is burned into our brains: draw baseline cortisol, give synthetic ACTH, wait an hour, draw post-ACTH cortisol. But what if I told you that baseline sample might be unnecessary? A comprehensive study published in Frontiers in Veterinary Scienceanalyzing over 1,000 ACTH stimulation tests from UK veterinary practices suggests the pre-ACTH cortisol adds no diagnostic value when you're already running the full stimulation test.